Detcon DM-100 - Manual (Page 28)

Model DM-100
DM-100 Instruction Manual Rev. 3.3 Page 24 of 40
Range Fault (FL09)
 Check validity of span gas with regulator and sample tubing in place using pull tube or other means
(check MFG date on cal gas cylinder). Use proper cal gas regulators and tubing for highly corrosive
gases (HF, HCI, Cl2, NH3, HBR, F2, etc.)
 Check for obstructions affecting cal gas hitting sensor face (including being wet, blocked, or
corroded). H2S sensors assemblies use DM-100 Bottom Housing Assembly with integral filter. Clean
or replace if necessary.
 If using Splashguard with Integral Cal Port, must use Calibration Wind Guard or air movement can
compromise span gas delivery
 Verify there is no background cross interference gases.
 Replace the plug-in toxic sensor.
Sensor Fault (FL10)
 Verify that the sensor cell is plugged into the ITM.
 Swap cell with a known good cell to see if the fault clears.
 Replace the sensor cell.
Zero Fault (FL11)
 The sensor zero baseline may have drifted lower. Perform Zero Calibration. Use Zero Air or N
2
source
(Section 3.3.1, Zero Calibration). Allow more time for zero stabilization if usuing a biased sensor type.
 Execute successful Span Calibration (Section 3.3.2, Span Calibration). Replace plug-in toxic sensor if
error continues.
Unstable Output/Sudden Spiking
 Verify that the field wiring is properly shielded and grounded.
 Verify that the power source is stable.
 Contact Detcon to optimize shielding and grounding.
 Add Detcon’s RFI Protection Circuit Accessory (PN 975-343002-007) if problem is proven RFI induced.
Nuisance Alarms
 Check condulet for accumulated water and abnormal corrosion on terminal board. If nuisance alarms
are happening at night, suspect condensation in condulet.
 Add or replace Detcon’s Condensation Prevention Packet (PN 960-202200-000).
 Investigate the presence of other target gases that are causing cross-interference signals.
 Determine if cause is RFI induced.
Unreadable Display (If a DM-100 display is installed.)
 If due to excessive sunlight, install a sunshade to reduce glare.
 Replace Display Assembly.
 Replace DM-100 Display.
Blank or Incorrect Reading on Display (If a DM-100 display is installed.)
 ITM has an internal fault, problem with display.
 Swap with a known-good ITM to determine if ITM is faulty.